"When a transmission is on our dyno,
utilizing infrared pyrometers, we monitor temperature at a
minimum of 12 key areas..."

The purpose of the gear box dyno is to accurately measure
power loss to the wheels due to drag in the gearbox. Many
shops attack the obvious culprits of drag: heavy
differentials, stock crown wheels, heavy oil, etc.. Although
these are all valid points, they are only the tip of the
iceberg. We have found through years of dyno testing, on a
multitude of transmission makes and models, that a large
percentage of drag within the gearbox lies in misalignments of
shafts and bearing bores at operating temperature. For
example, a bearing misalignment of as little as .004"
substantially increases drag and temperature. One of the keys
here is operating temperature.

When studying the gearbox drag and temperatures on a dyno
run, at factory recommended pre loads and settings,
there are sometimes significant drag and temperature
increases. Keep in mind that the aluminum or magnesium
cases, side covers and internal steel components of
these gearboxes expand at different rates while
temperature increases.

This is due to
the size, material and mass of the particular part, internal &
external webbing in the case and side cover design. Another
key issue we have found is the distortion and movement of left
hand side covers under load. It is important to locate the
side cover for optimum bearing alignment at operating
temperature under load.

When a transmission is on our dyno,
utilizing infrared pyrometers, we monitor temperature at a
minimum of 12 key areas. This allows us to see potential drag
problems in the gearbox before we ever take it apart. Once the
gearbox has been completely blue printed to our specifications
we are able to run the gearbox again on the dyno to document
the decrease in drag. In addition, this is also a useful
quality control tool to insure that the gear box runs properly
in all gear selections and has no leaks.

We
would be glad to answer any questions you may have
about your gearbox. Please
contact us for information on the services
mentioned above as well as gearbox rebuilds and
gearbox blueprinting.